1. Technical Field
This invention relates in general to computers and, more particularly, to a heat frame for use in a portable computer.
2. Description of the Related Art
For many years, the popularity of portable computers has risen as the size and weight of the portable computer has been reduced. Early portable computers were known as "luggable" computers, since they could be transported, but were only slightly smaller and lighter than comparable desktop computers. "Laptop" computers were smaller and lighter, but generally had reduced features and flexibility because most of the circuitry needed to be designed into the laptop motherboard without the option of expansion boards.
"Notebook" computers are significantly smaller and lighter than laptop computers. These computers can be carried easily in a briefcase. Two of the most important considerations in the usability of a notebook are the weight and thickness of the computer. It is very desirable to have a light, thin notebook computer.
One problem in weight and thickness reduction is their effect on cooling the internal components, especially the microprocessor. This is especially problematic with the move to higher frequency microprocessors which generate additional heat. To remove heat from the microprocessor, many prior art designs mount a heat sink opposite the microprocessor on a circuit board. Thermal vias are formed in the circuit board below the microprocessor to draw heat from the microprocessor to the heat sink. The heat sink dissipates heat to the area surrounding the microprocessor, which often causes hot spots to occur in areas of the housing which contact the user. Further, with little air movement within the housing, the heat transfer can be ineffective for high speed microprocessors.
Another option to remove heat is to attach a fan to the microprocessor to draw cool air over the microprocessor. While this technique is used in desktop machines in conjunction with high speed microprocessors, it is generally undesirable in notebook designs because of the additional space required by the fan. Additionally, the fan generates noise and uses additional power, neither of which is desirable in a notebook computer.
Therefore, a need has arisen for a more efficient and cost effective heat transfer mechanism.